<template>
  <div id="app">
    <div id="cover"></div>
    <Header></Header>   <!-- 使用组件 -->
    <todo></todo>
    <Footer></Footer>
  </div>
</template>

<script>
//1. 引入组件
import Header from "./todo/header.vue";
import Footer from './todo/footer.jsx'
import Todo from "./todo/todo.vue";
export default {
  //2.申明 用到的组件
  components: {
    Header,
    Footer,
    Todo
  }
};
</script>

<style lang="stylus" scoped>
#app {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  buttom: 0;
}

#cover {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  background-color: #999;
  opacity: 0.2;
  z-index: -1;
}
</style>